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153:. The three vesicles need to develop further into five brain vesicles but the space at the cranial end is limited. This causes the neural tube to bend ventrally at two flexures – the first at the cephalic flexure and the second at the cervical flexure. A third flexure is oriented in the opposite dorsal direction as the pontine flexure. By the fifth week further flexion has taken place and the five secondary brain vesicles have formed.
117:. The space into which the cranial part of the neural tube is developing is limited. This limitation causes the neural tube to bend, or flex, at two ventral flexures – the rostral cephalic flexure, and the caudal cervical flexure. It also bends dorsally into the pontine flexure. These flexures have formed by the time that the primary brain vesicles have developed into five
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The angle formed by the two ventral flexures, the cephalic flexure and the cervical flexure together, is a right angle in the ventral direction between the axis of the body and the axis of the brain. The pontine flexure is located between these two flexures.
180:, also known as the mesencephalic flexure, is the first flexure or bend, that forms in the region of midbrain. The caudal part of the midbrain and the rostral part of the hindbrain makes up a mibrain-hindbrain boundary region known as the
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at the caudal end. By the fourth week in the human embryo, at its cranial end, three swellings have formed as primary brain vesicles. These vesicles form the future
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Puelles, Eduardo; Martínez-De-La-Torre, Margaret; Watson, Charles; Puelles, Luis (2012). "Midbrain".
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184:. In human embryos, it generally occurs at the end of the 3rd week or the beginning of the 4th.
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Brain of human embryo of four and a half weeks, showing the three flexures
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232:. These two regions develop and fold dorsally at the pontine flexure.
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367:(11th. ed.). Lippincott William & Wilkins. p. 294.
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133:, from the future brain area at the cranial end, to the
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129:The neural tube has a longitudinal axis called the
67:(embryology)_by_E5.14.3.3.0.0.3 E5.14.3.3.0.0.3
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196:forms between the hindbrain and the spinal cord.
408:"Congenital basis of posterior fossa anomalies"
285:, Treasure Island (FL): StatPearls Publishing,
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469:Overview at nlm.nih.gov - online book
228:, and the myelencephalon becomes the
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474:Diagram at nlm.nih.gov - online book
406:Cotes, C; et al. (June 2015).
167:at the midbrain-hindbrain boundary.
319:10.1016/B978-0-12-369497-3.10010-X
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212:, forms the boundary between the
16:Part of the embryonic neural tube
220:. The metencephalon becomes the
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393:braininfo.rprc.washington.edu
347:braininfo.rprc.washington.edu
781:Embryology of nervous system
604:Cardiac neural crest complex
365:Langman's medical embryology
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412:The Neuroradiology Journal
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424:10.1177/1971400915576665
311:The Mouse Nervous System
119:secondary brain vesicles
94:form in the part of the
101:that develops into the
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115:primary brain vesicles
74:Anatomical terminology
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611:Truncal neural crest
599:Cranial neural crest
313:. pp. 337–359.
279:"Neuroanatomy, Pons"
509:Development of the
363:Sadler, TW (2010).
252:Saladin, K (2011).
125:Flexure development
121:in the fifth week.
581:Adult neurogenesis
534:Neural development
459:Embryology at UNSW
343:"Cervical flexure"
208:, also called the
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629:Rostral neuropore
389:"Pontine flexure"
230:medulla oblongata
182:isthmic organizer
165:Isthmic organizer
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188:Cervical flexure
178:cephalic flexure
172:Cephalic flexure
135:conus medullaris
105:. At four weeks
80:edit on Wikidata
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743:Otic placode
725:Lens placode
591:Neural crest
576:Neuropoiesis
559:Neural plate
519:Neurogenesis
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111:human embryo
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700:Neural tube
663:Basal plate
621:Neural tube
564:Neural fold
539:Neurulation
139:spinal cord
99:neural tube
44:Identifiers
776:Embryology
770:Categories
673:Neuroblast
658:Alar plate
638:Rhombomere
296:2022-09-02
283:StatPearls
236:References
226:cerebellum
715:Optic cup
668:Glioblast
634:Neuromere
549:Notochord
151:hindbrain
143:forebrain
96:embryonic
748:Otic pit
442:26246090
291:32809424
224:and the
216:and the
147:midbrain
131:neuraxis
92:flexures
22:Flexures
544:Neurula
527:General
433:4757284
137:of the
109:in the
55:flexura
39:Details
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149:, and
90:Three
103:brain
78:[
50:Latin
438:PMID
369:ISBN
323:ISBN
287:PMID
258:ISBN
222:pons
204:The
192:The
176:The
736:Ear
692:Eye
428:PMC
420:doi
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
